Digital photo albums are growing explosively in popularity—both number and size-due to the rapid popularization of digital cameras and mobile phone cameras in the last decade. These large image collections often require the annotation of some semantic information to facilitate browsing, manipulation and sharing of photos. In a typical family photo, for example, the information of when and where the photo was taken is helpful, but even more important is the information of who is portrayed in the photo. Therefore, face annotation is becoming an indispensable part of the management of photos and other images depicting people.
Unfortunately, in most conventional commercial systems, face annotation is based on elaborate, user-driven user interface designs. Although some efforts have been made to simplify photo labeling with a drag-and-drop interface, none contain break-through improvements automating the process although some use state-of-art face detection techniques. In each conventional system, relatively intensive operations are required to label and group faces in photos. Labeling each photo by hand according to the faces of the people pictured remains a tedious task. What is needed is an automatic/semi-automatic technique to enable rapid face annotation.